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Can we control the flatness of the surface of a thin film down to the level of individual atoms? Can we further make such an ultraflat surface on a wafer scale? For such purposes, the current deposition methods, including molecular beam epitaxy (MBE), atomic layer deposition (ALD) and conventional sputtering methods, are still not adequate. In this article, we introduce a novel thin film deposition technique developed by modifying a simple sputtering method to make atomically flat metallic surfaces and a new way to investigate the structural details of thin films grown at the atomic level. For thin film, heteroepitaxial growth of a crystalline film on a different crystalline substrate is usual, and the lattice mismatch between the crystalline film and the substrate occurring in heteroepitaxy produces many misfits at the interface, which create various defects, including dislocations and grain boundaries that eventually lead to a rough surface and the deterioration of the overall quality of the crystal. The metamorphic growth method utilizing the extended atomic distance mismatch (EADM) helps to achieve successful growth of thin films in spite of a large lattice mismatch by calculating the match for a relatively long period in advance. Having an ultraflat surface for thin films made of metals such as copper has many advantages. Several advantages and possible applications of metal thin films with ultraflat surfaces are introduced.

AIM To investigate the diagnostic performance of 18F-fluciclovine positron-emission tomography (PET) or combined PET and computed tomography (PET/CT) for diagnosis of primary cancer, preoperative lymph node (LN) staging, and detection of recurrent disease of prostate cancer (PCa) through a systematic review and meta-analysis. MATERIALS AND METHODS The PubMed and EMBASE databases were searched from the earliest available date of indexing through 31 December 2018, for studies evaluating the diagnostic performance of 18F-fluciclovine PET or PET/CT for the management of PCa patients. The sensitivities, specificities, and positive and negative likelihood ratios (LR+ and LR-) across the studies were calculated and summary receiver operating characteristic curves were constructed. RESULTS Across 13 studies (563 patients), the pooled sensitivity for 18F-fluciclovine PET or PET/CT for diagnosis of primary PCa was 0.87 (95% confidence interval [CI]: 0.77–0.93) and a pooled specificity of 0.84 (95% CI: 0.68–0.93). For LN staging, the pooled sensitivity was 0.56 (95% CI: 0.37–0.74) and a pooled specificity of 0.98 (95% CI: 0.88–1.00). For detection of recurrent disease, the pooled sensitivity was 0.79 (95% CI: 0.60–0.91) and a pooled specificity of 0.69 (95% CI: 0.59–0.77). In meta-regression analysis, no definite variable was the source of the study heterogeneity. CONCLUSION The current meta-analysis showed the moderate sensitivity and specificity of 18F-fluciclovine PET or PET/CT for the diagnosis of primary cancer, preoperative LN staging, and detection of recurrent PCa. Further large multicentre studies will be necessary to substantiate the diagnostic accuracy of 18F-fluciclovine PET/CT for management of PCa patients.

High-quality epitaxial Cu2O (111) thin films were obtained from single-crystal Cu (111) thin films by rapid thermal oxidation at 800 °C. X-ray diffraction and electron backscattering diffraction analyses indicated that the films were pure Cu2O phase and well aligned along the [111] direction. Microscopic imaging of the films revealed a unique surface morphology in the form of a plateau grain network a few microns in size, which has never been achieved previously in this semiconductor. From the absorption coefficient and its first derivative, all of the characteristic optical transitions from the yellow to the indigo series, as well as excitonic transitions, were consistent with those observed from high-quality bulk Cu2O. The exceptional quality of our films was further verified by a very weak defect-induced photoluminescence, which typically dominates in natural-growth Cu2O crystals. We believe that our study represents a step towards the synthesis of high-quality oxide films having unusual surface morphologies.

The single-crystalline copper (Cu) thin film is a platform substrate for the growth of numerous materials and has been a significant issue for the scientific community. The primary concern is the i...

AIM To investigate the predictive value of integrated 2-[18F]-fluoro-2-deoxy- d- glucose (18F-FDG) positron-emission tomography/computed tomography (PET/CT) for the prediction of programmed death ligand 1 (PD-L1) expression in solid tumours via a systematic review and meta-analysis. MATERIALS AND METHODS The PubMed, Cochrane, and EMBASE databases, from the earliest available date of indexing through 31 October 2020, were searched for studies evaluating the diagnostic performance of 18F-FDG PET/CT for prediction of PD-L1 expression in solid tumours other than lung cancer. RESULTS Across seven studies (473 patients), the pooled sensitivity for 18F-FDG PET/CT was 0.75 (95% confidence interval [CI]: 0.65–0.82) without heterogeneity (I2 = 47.2, p=0.08) and a pooled specificity of 0.73 (95% CI: 0.64–0.81) with heterogeneity (I2 = 53.8, p=0.04). Likelihood ratio (LR) syntheses gave an overall positive likelihood ratio (LR+) of 2.8 (95% CI: 2.1–3.7) and negative likelihood ratio (LR–) of 0.35 (95% CI: 0.26–0.47). The pooled diagnostic odds ratio (DOR) was 8 (95% CI: 5–13). Hierarchical summary receiver operating characteristic (ROC) curve and indicates that the area under the curve was 0.80 (95% CI: 0.77–0.84). CONCLUSION The current meta-analysis showed a moderate sensitivity and specificity of 18F-FDG PET/CT for the prediction of PD-L1 expression in solid tumours. At present, the literature regarding the use of 18F-FDG PET/CT for the prediction of PD-L1 expression in solid tumours still limited; thus, further large multicentre studies would be necessary to substantiate the diagnostic accuracy of 18F-FDG PET/CT for prediction of PD-L1 expression in solid tumours.

Stochastic inhomogeneous oxidation is an inherent characteristic of copper (Cu), often hindering color tuning and bandgap engineering of oxides. Coherent control of the interface between metal and metal oxide remains unresolved. We demonstrate coherent propagation of an oxidation front in single-crystal Cu thin film to achieve a full-color spectrum for Cu by precisely controlling its oxide-layer thickness. Grain boundary-free and atomically flat films prepared by atomic-sputtering epitaxy allow tailoring of the oxide layer with an abrupt interface via heat treatment with a suppressed temperature gradient. Color tuning of nearly full-color RGB indices is realized by precise control of oxide-layer thickness; our samples covered ~50.4% of the sRGB color space. The color of copper/copper oxide is realized by the reconstruction of the quantitative yield color from oxide pigment (complex dielectric functions of Cu2O) and light-layer interference (reflectance spectra obtained from the Fresnel equations) to produce structural color. We further demonstrate laser-oxide lithography with micron-scale linewidth and depth through local phase transformation to oxides embedded in the metal, providing spacing necessary for semiconducting transport and optoelectronics functionality., Comment: 38 pages

Realizing laterally continuous, ultraflat silver (Ag) single-crystal films is a significant technological challenge. Ag thin film grown on various hetero-substrates has been used in numerous applications, due to its superior electrical and optical properties. To exploit these properties without degradation and apply these films to high-precision patterning, surface plasmonics, and so on, a high-quality thin film having an ultraflat surface and few grain boundaries is needed. A zinc oxide (ZnO) buffer layer can be used to facilitate the growth of a single-crystalline Ag thin film on a sapphire (Al2O3) substrate. ZnO films deposited on Al2O3 substrates have grain boundaries; however, Ag films grown on ZnO are nearly grain-free and close to single-crystalline quality. This can be explained by the exceptionally small extended atomic distance mismatch, of ~0.08%, between Ag and Al2O3, in which the ninth Ag atom and the eighth Al atom are matched in terms of coherence and periodicity. A modified radio frequency sputtering system with a single-crystal Ag target enabled wafer-scale growth of ultraflat, grain-free Ag films. The proposed approach using a ZnO buffer provides a new method for fabricating Ag films with high adhesion, anti-oxidative stability, and superior optical properties, and allows for easy nano-patterning.

BACKGROUND AND OBJECTIVE Epitope spreading is one of valid mechanisms operating in immunopathological processes of infection-induced autoimmune diseases. We hypothesized that the peptide 19 from Porphyromonas gingivalis heat shock protein (HSP) 60 (Pep19) may be the dominant epitope from which epitope-specific immune response to subdominant epitopes may diversify sequentially into autoimmune responses directed at human neoepitopes in P. gingivalis-induced periodontitis and autoimmune diseases. However, the exact feature and mechanism on how Pep19 may drive epitope spreading into human autoantigens in chronic periodontitis or P. gingivalis-induced experimental periodontitis has not been clarified. The present study was performed with the following specific aims: (i) to delineate retrospectively the features of epitope spreading by human cross-sectional analysis; (ii) to demonstrate prospectively the epitope spreading into new antigenic determinants in an ordered, predictable and sequential manner in experimental periodontitis; and (iii) to clarify the mechanism on how immunization with Pep19 may mobilize helper T cells or elicit B-cell responses to human autoantigens and neoantigen. MATERIAL AND METHODS The study was devised for two independent investigations - a cross-sectional analysis on clinical subjects and a prospective analysis on experimental periodontitis - each being subdivided further into two additional independent observations. Cross-sectional dot immunoblot pattern against a panel of peptides of P. gingivalis HSP60 and human HSP60 was performed among age-dependent healthy subjects and between healthy subjects, patients with chronic periodontitis and patients with autoimmune disease, to identify epitope spreading. A peptide-specific T-cell line was established for phenotype analysis and for proliferation assay to an array of identical peptides. An identical prospective analysis was performed in P. gingivalis-induced experimental periodontitis or in Pep19-immunized mice. Cross-reactivity of anti-Pep19 monoclonal antibody was also investigated. RESULTS A dominant immune response exclusively to Pep19 prevailed in healthy human subjects (before the age of 40) and mice that persisted in chronic periodontitis and autoimmune diseases without being replaced further by subsequent subdominant epitopes. A sequential epitope spreading provoked by Pep19 to subdominant autoantigen peptide 19 from human HSP60 (Hu19) in most healthy human subjects and mice, and to autoantigen peptide 9 from human HSP60 (Hu9) and neoantigen oxidized low-density lipoprotein (ox-LDL) in P. gingivalis-induced chronic periodontitis and autoimmune diseases could be demonstrated in a reproducible and predictable manner. T-cell proliferative activity to multiple autoantigens Hu19, Hu9 and ox-LDL, and cross-reactivity of anti-Pep19 monoclonal antibody to these epitopes may be proposed as cellular and molecular mechanisms responsible for the phenomenon. Moreover, the predictive value of Pep19 for Hu9 increased remarkably in the disease group when compared with that of the healthy group. CONCLUSION Taken together, epitope spreading to Hu19, Hu9 and ox-LDL provoked by Pep19 could be proposed as a solid phenomenon observed in P. gingivalis-induced chronic periodontitis and infection-induced autoimmune diseases in a reproducible and predictable manner. T-cell proliferative activity to these peptides and cross-reactivity of anti-Pep19 antibodies to multiple human autoantigens could be proposed as cellular and molecular mechanisms responsible for this phenomenon.

Pedestrians not only walk along pedestrian pathways, but also choose unusual routes such as passing through buildings or crossing large scale open spaces. This study defines these unusual paths as social path, and includes them into one of the pedestrian road categories. Previous pedestrian accessibility and route choice studies could not evaluate correctly the space connectivity or optimal route because the social path was not considered properly. Therefore, this study analyzes the effectiveness of the social path in view of space connectivity focused on Coex and Seoul stations in Seoul, which are representative transit oriented development(TOD) areas. Global integration, which is widely used in network analysis, is selected (as performance index) to identify the space hierarchy and define new pedestrian links. The study results show that the network connectivity is improved especially in the main streets and social paths. This study demonstrated that the social path should be considered in finding the pedestrian optimal route from the practical perspective. Keywords global integration; pedestrian accessibility; pedestrian route choice; social path; space syntax ; 공간 통합도; 보행 접근성; 보행 경로 선택 Language: ko

This study analyzes the influence factors on elderly pedestrian accident. Elderly people are easy to be badly injured by car accidents compared to younger people. Therefore, various plans and measures are required to protect elderly pedestrian from accidents. However, pedestrian accidents studies only focused on microscopic factors such as attribute of driver, pedestrian, road design. In order to prevent pedestrian accident and reduce the severity of the accident, not only microscopic factors but macroscopic variables suc h as urban planning and facility should be considered. In this regard, this study develops an ordered probit model introduced the characteristics of urban facility which were not considered in the previous studies. The result shows that there is higher level of accident severity in such areas as large commercial area, well-developed area with transportation infrastructure service and non-pedestrian safety zone. Thus, various and appropriate countermeasures should be prepared in order that pedestrian accident can be prevented in the areas mentioned above. In addition to the aforementioned variables, it is revealed that other variables including vehicle speed, gender and age of pedestrian, weather condition, type of vehicle, etc. partly affect the severity of pedestrian accident.

Background: F-18 FDG PET/CT is superior to CT imaging in identifying metastatic mediastinal lymph node (MLN) involvement in NSCLC. However, the accuracy of PET in nodal staging is substantially reduced by false increases in the inflammatory nodes. The efficacy of this technique is controversial, especially in regions endemic for the granulomatous disease. Here, we determined the qualitative and quantitative parameters of PET/CT for evaluation of mediastinal nodes to distinguish between malignant and benign lesions. Methods: 27 patients with pathologically documented NSCLC who showed bilateral F-18 FDG-avid MLNs on pre-treatment staging PET/CT image were included. 104 MLNs were analysed through EBUS-TBNA or MLN dissection. The MLN with prominent F-18 FDG uptake compared with other F-18 FDG-avid LNs via visual assessment was qualitatively considered as metastasis. The SUVmax of LN and SUVmax of LN to the liver and blood pool were calculated. SUVmax/contra was obtained to identify metastatic MLNs. Results: The qualitative evaluation showed sensitivity, specificity, PPV, and NPV for separating metastatic LN from benign reactive hyperplasia of 66.7%, 87.0%, 74.3%, and 88.2%, respectively. SUVmax/contra was significantly higher for metastatic LNs than benign lesions. Conclusions: Qualitative interpretation of PET/CT was superior to quantitative parameters in discriminating metastatic LNs from benign reactive hyperplasia in patients with bilateral F-18 FDG-avid mediastinal LNs. We suggest SUVmax/contra may aid in the interpretation of mediastinal nodal staging in patients with NSCLC.

High-quality, single-crystal-like Cu2O thin films of various thicknesses (10 nm–45 nm) were prepared at a low temperature (150 °C) by controlling layer-by-layer oxidation of wafer-scale Cu thin films sputtered along the (111) direction using a pure single-crystal Cu target. The cross-sectional images of the thin films reveal high crystallinity of Cu2O layers except for 60° twinning in the sequential stacking order as evidenced by high-resolution transmission electron microscopy, which is consistent with the absence of the photoluminescence (PL) signals arising from atomic-scale vacancies. The optical properties of our Cu2O films were investigated using temperature-dependent PL and Raman spectroscopy. All of the Cu2O thin films exhibit characteristic band-to-band transitions together with the series of yellow excitonic transitions slightly below the fundamental bandgap. The spectral locations for the PL are approximately consistent with those for the bulk counterpart. The excellent optical quality of our Cu2O was further demonstrated by significantly reduced quasi-direct transition that occurs at symmetry-breaking crystal imperfection, which relaxes the stringent momentum conservation rule. We identified the three main Raman scattering modes of the Cu2O thin films, where the two forbidden modes of Γ15(1) and Γ12−+Γ25− are resonantly allowed by the proximity of the incident photon energy to the green bandgap. We believe that our synthesis technique can be utilized for the preparation of single-crystal-like metal oxide thin films at low production temperatures with precise thickness control for the development of novel optoelectronic devices and for the exploration of the nanoscale light-matter interaction as well.

Jeong E, Lee J-Y, Kim S-J, Choi J. Predominant immunoreactivity of Porphyromonas gingivalis heat shock protein in autoimmune diseases. J Periodont Res 2012; 47: 811–816. © 2012 John Wiley & Sons A/S Background and Objective: Autoimmune diseases, including atherosclerosis, diabetes mellitus and rheumatoid arthritis, can be triggered and aggravated by the pathogen-driven antigenic peptide from Porphyromonas gingivalis HSP60. P. gingivalis is the major pathogen of chronic periodontitis, which is a global epidemic prevalent in two-thirds of the adult population. The monoclonal antibody raised against peptide 19 (Pep19: TLVVNRLRGSLKICAVKAPG) from P. gingivalis HSP60 was polyreactive to the human homolog. The aim of this study was to determine if Pep19 from P. gingivalis HSP60 manifests itself as a predominant antigen in infection-triggered autoimmune diseases. Material and Methods: Pep19 from P. gingivalis HSP60, Mycobacterium tuberculosis HSP60 and Chlamydia pneumoniae HSP60 was synthesized for comparative recognition by the sera from patients with atherosclerosis, type 2 diabetes and rheumatoid arthritis, all with ongoing periodontal disease, and by the sera of a control group of patients with periodontal disease but with no history of atherosclerosis, type 2 diabetes or rheumatoid arthritis. Results: Of the Pep19 peptides from P. gingivalis HSP60, M. tuberculosis HSP60 and C. pneumoniae HSP60, Pep19 from P. gingivalis HSP60 was the peptide epitope predominantly and most consistently recognized by the serum samples of the four disease groups (chronic periodontitis, atherosclerosis, type 2 diabetes mellitus and rheumatoid arthritis). Conclusion: Seroreactivity to Pep19 of P. gingivalis HSP60, an oral pathogen, was predominant in patients with autoimmune disease with ongoing periodontal disease.

BACKGROUND AND STUDY AIMS: Endoscopic transpapillary gallbladder drainage for symptomatic gallbladder disease is a safe and effective bridge therapy in patients at high risk for surgery or who have terminal liver disease and are awaiting transplantation. However, there are few reports on long-term results in terms of stent patency and clinical course. Our study was designed to investigate the long-term patency and clinical course after endoscopic transpapillary gallbladder stenting (ETGS) in patients with symptomatic gallbladder disease. PATIENTS AND METHODS: A total of 29 patients who were unsuitable for cholecystectomy underwent ETGS from June 2006 to March 2010 using a 7-Fr double-pigtail stent between the gallbladder and the duodenum. Their clinical progress, adverse events, and stent patency after ETGS were recorded prospectively in two tertiary referral centers. RESULTS: Technically, ETGS was successful in 23 (79.3 %) of the 29 patients. The mean procedure time was 22.4 ± 11.5 min. Postprocedure adverse events were mild pancreatitis (8.7 %) and cholestasis (8.7 %), all of which resolved with conservative management. During the follow-up period (median 586 days, range 11 – 1403 days), 20 patients were analyzed as per protocol, and scheduled follow-up was performed. Late adverse events developed in four patients (20 %), including distal migration (n = 2), cholangitis (n = 1), and recurrent biliary pain (n = 1). The remaining 16 patients were followed for more than 12 months (nine patients were followed for more than 24 months). Median stent patency was 760 days, as determined by the Kaplan-Meier method. CONCLUSIONS: As a primary therapy, ETGS is technically feasible and effective in patients who are unsuitable for cholecystectomy. ETGS may also provide long-term stent patency without the need for scheduled stent exchanges.

The 3-D gradient-echo (GRE) sequence allows thinner sections and better resolution of biliary obstruction. When the presence of biliary obstruction is identified using magnetic resonance cholangiopancreatography, the addition of the 3-D GRE sequence may be helpful for diagnosing biliary obstruction. By showing the changes in the bile duct wall, within the duct lumen and around the bile duct, this technique can be helpful for distinguishing benign from malignant stricture as well as a stone from an enhancing intraluminal mass.

Background and study aims Various clinical and endoscopic factors have been proposed and used as predictors of endoscopic treatment failure in bleeding peptic ulcers. Recently, several endoscopic factors have been considered to be more significant than various clinical factors, except for shock. Detailed knowledge of which endoscopic factors can be classified as predictors of rebleeding following endoscopic hemostasis is needed. This study describes newly defined endoscopic variables and evaluates their usefulness as predictors of endoscopic treatment failure. Patients and methods Between January 1996 and April 1999, diagnostic and therapeutic endoscopies were carried out in 143 patients with active bleeding peptic ulcers. Nine clinical and eight endoscopic variables were studied. Endoscopic factors were classified by three types of stigmata bleeding, 14 locations, two ulcer sizes, three ulcer bases, three visible vessel colors, two ulcer depths, two margin shapes, and three endoscopic treatment methods (injection, hemoclipping, and combination). Results 36 patients experienced rebleeding (25.2 %), 11 patients needed operations (7.7 %) and five deaths occurred (3.5 %). In univariate analysis, rebleeding was significantly related to: i) presence of spurting activity (odds ratio [OR] = 4.91, P = 0.006), ii) ulcer size larger than 2 cm (OR = 2.78, P = 0.017); and iii) location in stomach (OR = 2.81, P = 0.026). Clinical variables including age, shock, and initial hemoglobin levels were not significantly related to rebleeding. In multiple logistic regression using selected significant variables, presence of spurting activity remained a significant independent predictor of rebleeding (adjusted OR = 6.48, P = 0.003). Conclusion Our data support the hypothesis that endoscopic factors are more important than clinical ones when predicting rebleeding of peptic ulcers. Based on statistical analysis of risk factors, the ulcers most likely to rebleed after endoscopic therapy are those which are located in the stomach, are greater than 2 cm in diameter and exhibit oozing or spurting of blood.

We have observed a phenomenon associated with a transition from vertical alignment to an optically compensated splay structure. With rubbed homeotropic alignment in parallel directions, the device shows vertical alignment but the liquid crystals (LCs) are twisted 180° in the absence of an electric field. Depending on the voltage applied, two different configurations of LCs are possible. After applying a critical voltage, the LC configuration becomes splayed such that the middirector lies parallel to the substrate and around it, and a hybrid structure forms symmetrically. A method for obtaining the transition and the electro-optic characteristics of the device is discussed.

The circuitry and components of a Hall measurement kit were replaced with single-crystal copper (SCC) wires and parts prepared by a novel wire fabrication process. This process preserved the grain-free structure of SCC grown by the Czochralski method. The new kit was used to determine, with greatly improved precision, the electrical coefficients such as carrier density and mobility, establish the reproducibility of the measured values, and define the semiconductor type. The observed reduction in electrical signal losses and distortion has been attributed to grain boundary elimination.

Aim To differentiate remnant tumour from postoperative changes on short-term follow-up magnetic resonance imaging (MRI) or combined positron-emission tomography (PET) and computed tomography (CT) after inadequate primary resection of malignant soft-tissue tumours. Materials and methods From January 2007 through September 2010, 35 patients (18 women and 17 men; mean age 48 years; age range 18–78 years) who underwent MRI and PET-CT within 64 days after surgery for malignant soft-tissue tumours were included. MRI images were assessed for the following findings: the presence of delineated enhancing portions; fascial thickening; and fluid or haematomas with measurable wall thickening. The PET-CT data were analysed using the standardized uptake value (SUV) and the uptake pattern. Results The correlation of tumour grade and the presence of remnant tumour was significant (p = 0.026). After re-excision, remnant tumour was demonstrated in 15 patients and no tumour cells were discovered in 20 patients. The finding of focally delineated enhancing portions on MRI images and the SUVmax on PET-CT analysis were significantly correlated with the remnant tumour (each p = 0.001 and p = 0.036). Conclusions To evaluate the presence of remnant tumour after inadequate excision of malignant soft-tissue tumours, an MRI finding of a focally enhancing area and an SUVmax of >2 on PET-CT might be helpful factors. The coexistence of these two findings would be even more helpful for the detection of residual tumours.

Background and study aims The endoscopic hemostatic method has been introduced as a safe and effective mechanical approach to hemostasis for upper gastrointestinal bleeding related to Mallory-Weiss syndrome (MWS). However, the indications for when to use endoscopic treatment are debatable because many patients need only medical observation. The study was designed to evaluate the necessity and efficacy of endoscopic hemostasis in upper gastrointestinal bleeding related to MWS. Patients and methods From July 1994 to May 2000, we conducted a clinical trial in 76 patients who were found by endoscopy to have active bleeding (I, spurting; II, oozing), protruding visible vessels (III), and/or adherent clots (IV). Two study periods can be differentiated: in the first 3 years endoscopic treatment (n = 30) was prospectively analyzed and in the final 3 years medical treatment (n = 46) was analyzed in both cases to compare the outcome in MWS bleeding II-IV. In the first study period, in addition, endoscopic treatment was randomised to an injection method, using a mixture of hypertonic saline and epinephrine (HSE) (n = 14) and a hemoclipping or band ligation method (n = 16). Results Rebleeding was observed in four of 14 patients who had received endoscopic hemostasis with HSE injection and one of 46 patients who had been managed with medical treatment. No rebleeding was found following hemoclipping or band ligation. While all rebleeding was in bleeding stigmata of the I (1) and II (4) grades, there was no rebleeding in protruding visible vessels (III) or in adherent clots (IV), regardless of treatment methods. Conclusions Our results suggested that endoscopic hemostasis is not necessary in patients without active bleeding stigmata, and the mechanical hemostatic method is more effective than HSE injection in patients with active bleeding stigmata.